The Physical and Mental Metaphors (PMM) task and its validation in schizophrenia: a tool for rapid assessment of figurative language comprehension, between pragmatics and symptoms

Difficulties in figurative language understanding are largely documented as part of a broader pragmatic impairment, especially in psychosis. Among figurative domains, metaphor stands out as a significant predictor of functioning, in addition to exhibiting meaningful associations with psychopathological and cognitive features. Yet, the assessment of metaphor comprehension remains a niche area, also due to the lack of reliable and valid tools. Here, we examined the psychometric properties of a rapid test of metaphor comprehension, the Physical and Mental Metaphors (PMM) task, involving a sample of 143 patients with schizophrenia and 57 controls. Findings provide robust support for the PMM reliability and validity. First, internal consistency was satisfactory, and the factorial structure aligned with theoretical assumptions. Second, the PMM demonstrated good validity, being strongly correlated with the pragmatic profile of patients as measured with a standard tool such as the Assessment of Pragmatics and Cognitive Substrates (APACS) test, showing also relevant associations with symptomatology, in particular abstract thinking and the broader domains of disorganization and negative symptoms, as well as weakly with Theory of Mind and global cognition. Third, the PMM task proved highly effective both in discriminating between individuals with and without pragmatic deficit, as detected via APACS, and in distinguishing patients from healthy controls.Taken together, these results indicate that the PMM task captures a specific impairment in figurative language and the general pragmatic vulnerability characteristic of schizophrenia, at the interface between symptoms. As such, it represents a valuable tool for detecting communicative disorders, characterizing symptoms and complementing the diagnostic process.